[RFC,41/48] RISC-V: KVM: Add host side support to handle COVG SBI calls.

Message ID	20230419221716.3603068-42-atishp@rivosinc.com
State	Changes Requested
Headers	show Return-Path: <kvm-riscv-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org> From: Atish Patra <atishp@rivosinc.com> To: linux-kernel@vger.kernel.org Cc: Rajnesh Kanwal <rkanwal@rivosinc.com>, Atish Patra <atishp@rivosinc.com>, Alexandre Ghiti <alex@ghiti.fr>, Andrew Jones <ajones@ventanamicro.com>, Andrew Morton <akpm@linux-foundation.org>, Anup Patel <anup@brainfault.org>, Atish Patra <atishp@atishpatra.org>, =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= <bjorn@rivosinc.com>, Suzuki K Poulose <suzuki.poulose@arm.com>, Will Deacon <will@kernel.org>, Marc Zyngier <maz@kernel.org>, Sean Christopherson <seanjc@google.com>, linux-coco@lists.linux.dev, Dylan Reid <dylan@rivosinc.com>, abrestic@rivosinc.com, Samuel Ortiz <sameo@rivosinc.com>, Christoph Hellwig <hch@infradead.org>, Conor Dooley <conor.dooley@microchip.com>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Guo Ren <guoren@kernel.org>, Heiko Stuebner <heiko@sntech.de>, Jiri Slaby <jirislaby@kernel.org>, kvm-riscv@lists.infradead.org, kvm@vger.kernel.org, linux-mm@kvack.org, linux-riscv@lists.infradead.org, Mayuresh Chitale <mchitale@ventanamicro.com>, Palmer Dabbelt <palmer@dabbelt.com>, Paolo Bonzini <pbonzini@redhat.com>, Paul Walmsley <paul.walmsley@sifive.com>, Uladzislau Rezki <urezki@gmail.com> Subject: [RFC 41/48] RISC-V: KVM: Add host side support to handle COVG SBI calls. Date: Wed, 19 Apr 2023 15:17:09 -0700 Message-Id: <20230419221716.3603068-42-atishp@rivosinc.com> In-Reply-To: <20230419221716.3603068-1-atishp@rivosinc.com> References: <20230419221716.3603068-1-atishp@rivosinc.com> MIME-Version: 1.0 preview: From: Rajnesh Kanwal <rkanwal@rivosinc.com> Adding host side support to allow memory sharing/unsharing. Host needs to check if the page has been already assigned (converted) to a TVM or not. If yes, that page needs to be reclaimed before sharin [...] Content analysis details: (0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at https://www.dnswl.org/, no trust [2607:f8b0:4864:20:0:0:0:62e listed in] [list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid Precedence: list Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kvm-riscv" <kvm-riscv-bounces@lists.infradead.org> Errors-To: kvm-riscv-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org
Series	RISC-V CoVE support \| expand [RFC,00/48] RISC-V CoVE support [RFC,01/48] mm/vmalloc: Introduce arch hooks to notify ioremap/unmap changes [RFC,02/48] RISC-V: KVM: Improve KVM error reporting to the user space [RFC,03/48] RISC-V: KVM: Invoke aia_update with preempt disabled/irq enabled [RFC,04/48] RISC-V: KVM: Add a helper function to get pgd size [RFC,05/48] RISC-V: Add COVH SBI extensions definitions [RFC,06/48] RISC-V: KVM: Implement COVH SBI extension [RFC,07/48] RISC-V: KVM: Add a barebone CoVE implementation [RFC,08/48] RISC-V: KVM: Add UABI to support static memory region attestation [RFC,09/48] RISC-V: KVM: Add CoVE related nacl helpers [RFC,10/48] RISC-V: KVM: Implement static memory region measurement [RFC,11/48] RISC-V: KVM: Use the new VM IOCTL for measuring pages [RFC,12/48] RISC-V: KVM: Exit to the user space for trap redirection [RFC,13/48] RISC-V: KVM: Return early for gstage modifications [RFC,14/48] RISC-V: KVM: Skip dirty logging updates for TVM [RFC,15/48] RISC-V: KVM: Add a helper function to trigger fence ops [RFC,16/48] RISC-V: KVM: Skip most VCPU requests for TVMs [RFC,17/48] RISC-V : KVM: Skip vmid/hgatp management for TVMs [RFC,18/48] RISC-V: KVM: Skip TLB management for TVMs [RFC,19/48] RISC-V: KVM: Register memory regions as confidential for TVMs [RFC,20/48] RISC-V: KVM: Add gstage mapping for TVMs [RFC,21/48] RISC-V: KVM: Handle SBI call forward from the TSM [RFC,22/48] RISC-V: KVM: Implement vcpu load/put functions for CoVE guests [RFC,23/48] RISC-V: KVM: Wireup TVM world switch [RFC,24/48] RISC-V: KVM: Update timer functionality for TVMs. [RFC,25/48] RISC-V: KVM: Skip HVIP update for TVMs [RFC,26/48] RISC-V: Add COVI extension definitions [RFC,27/48] RISC-V: KVM: Implement COVI SBI extension [RFC,28/48] RISC-V: KVM: Add interrupt management functions for TVM [RFC,29/48] RISC-V: KVM: Skip AIA CSR updates for TVMs [RFC,30/48] RISC-V: KVM: Perform limited operations in hardware enable/disable [RFC,31/48] RISC-V: KVM: Indicate no support user space emulated IRQCHIP [RFC,32/48] RISC-V: KVM: Add AIA support for TVMs [RFC,33/48] RISC-V: KVM: Hookup TVM VCPU init/destroy [RFC,34/48] RISC-V: KVM: Initialize CoVE [RFC,35/48] RISC-V: KVM: Add TVM init/destroy calls [RFC,36/48] RISC-V: KVM: Read/write gprs from/to shmem in case of TVM VCPU. [RFC,37/48] RISC-V: Add COVG SBI extension definitions [RFC,38/48] RISC-V: Add CoVE guest config and helper functions [RFC,39/48] RISC-V: Implement COVG SBI extension [RFC,40/48] RISC-V: COVE: Add COVH invalidate, validate, promote, demote and remove APIs. [RFC,41/48] RISC-V: KVM: Add host side support to handle COVG SBI calls. [RFC,42/48] RISC-V: Allow host to inject any ext interrupt id to a CoVE guest. [RFC,43/48] RISC-V: Add base memory encryption functions. [RFC,44/48] RISC-V: Add cc_platform_has() for RISC-V for CoVE [RFC,45/48] RISC-V: ioremap: Implement for arch specific ioremap hooks [RFC,46/48] riscv/virtio: Have CoVE guests enforce restricted virtio memory access. [RFC,47/48] RISC-V: Add shared bounce buffer to support DBCN for CoVE Guest. [RFC,48/48] drivers/hvc: sbi: Disable HVC console for TVMs

diff --git a/arch/riscv/include/asm/kvm_cove.h b/arch/riscv/include/asm/kvm_cove.h index 4367281..afaea7c 100644 --- a/arch/riscv/include/asm/kvm_cove.h +++ b/arch/riscv/include/asm/kvm_cove.h @@ -31,6 +31,9 @@ #define get_order_num_pages(n) (get_order(n << PAGE_SHIFT)) +#define get_gpr_index(goffset) \ + ((goffset - KVM_ARCH_GUEST_ZERO) / (__riscv_xlen / 8)) + /* Describe a confidential or shared memory region */ struct kvm_riscv_cove_mem_region { unsigned long hva; @@ -139,7 +142,8 @@ int kvm_riscv_cove_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run); int kvm_riscv_cove_vm_measure_pages(struct kvm *kvm, struct kvm_riscv_cove_measure_region *mr); int kvm_riscv_cove_vm_add_memreg(struct kvm *kvm, unsigned long gpa, unsigned long size); -int kvm_riscv_cove_gstage_map(struct kvm_vcpu *vcpu, gpa_t gpa, unsigned long hva); +int kvm_riscv_cove_handle_pagefault(struct kvm_vcpu *vcpu, gpa_t gpa, + unsigned long hva); /* Fence related function */ int kvm_riscv_cove_tvm_fence(struct kvm_vcpu *vcpu); @@ -179,8 +183,9 @@ static inline int kvm_riscv_cove_vm_measure_pages(struct kvm *kvm, { return -1; } -static inline int kvm_riscv_cove_gstage_map(struct kvm_vcpu *vcpu, - gpa_t gpa, unsigned long hva) {return -1; } +static inline int kvm_riscv_cove_handle_pagefault(struct kvm_vcpu *vcpu, + gpa_t gpa, unsigned long hva) { return -1; } + /* TVM interrupt managenet via AIA functions */ static inline int kvm_riscv_cove_aia_init(struct kvm *kvm) { return -1; } static inline int kvm_riscv_cove_vcpu_inject_interrupt(struct kvm_vcpu *vcpu, diff --git a/arch/riscv/include/asm/kvm_cove_sbi.h b/arch/riscv/include/asm/kvm_cove_sbi.h index b554a8d..c930265 100644 --- a/arch/riscv/include/asm/kvm_cove_sbi.h +++ b/arch/riscv/include/asm/kvm_cove_sbi.h @@ -59,6 +59,10 @@ int sbi_covh_create_tvm_vcpu(unsigned long tvmid, unsigned long tvm_vcpuid, int sbi_covh_run_tvm_vcpu(unsigned long tvmid, unsigned long tvm_vcpuid); +int sbi_covh_add_shared_pages(unsigned long tvmid, unsigned long page_addr_phys, + enum sbi_cove_page_type ptype, + unsigned long npages, + unsigned long tvm_base_page_addr); int sbi_covh_tvm_invalidate_pages(unsigned long tvmid, unsigned long tvm_base_page_addr, unsigned long len); diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h index b10c896..5b37a12 100644 --- a/arch/riscv/include/asm/kvm_vcpu_sbi.h +++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h @@ -66,5 +66,8 @@ extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_hsm; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_dbcn; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_experimental; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_vendor; +#ifdef CONFIG_RISCV_COVE_HOST +extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_covg; +#endif #endif /* __RISCV_KVM_VCPU_SBI_H__ */ diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h index ac3def0..2a24341 100644 --- a/arch/riscv/include/uapi/asm/kvm.h +++ b/arch/riscv/include/uapi/asm/kvm.h @@ -148,6 +148,7 @@ enum KVM_RISCV_SBI_EXT_ID { KVM_RISCV_SBI_EXT_EXPERIMENTAL, KVM_RISCV_SBI_EXT_VENDOR, KVM_RISCV_SBI_EXT_DBCN, + KVM_RISCV_SBI_EXT_COVG, KVM_RISCV_SBI_EXT_MAX, }; diff --git a/arch/riscv/kvm/Makefile b/arch/riscv/kvm/Makefile index 8c91551..31f4dbd 100644 --- a/arch/riscv/kvm/Makefile +++ b/arch/riscv/kvm/Makefile @@ -31,4 +31,4 @@ kvm-y += aia.o kvm-y += aia_device.o kvm-y += aia_aplic.o kvm-y += aia_imsic.o -kvm-$(CONFIG_RISCV_COVE_HOST) += cove_sbi.o cove.o +kvm-$(CONFIG_RISCV_COVE_HOST) += cove_sbi.o cove.o vcpu_sbi_covg.o diff --git a/arch/riscv/kvm/cove.c b/arch/riscv/kvm/cove.c index 154b01a..ba596b7 100644 --- a/arch/riscv/kvm/cove.c +++ b/arch/riscv/kvm/cove.c @@ -44,6 +44,18 @@ static void kvm_cove_local_fence(void *info) kvm_err("local fence for TSM failed %d on cpu %d\n", rc, smp_processor_id()); } +static void cove_delete_shared_pinned_page_list(struct kvm *kvm, + struct list_head *tpages) +{ + struct kvm_riscv_cove_page *tpage, *temp; + + list_for_each_entry_safe(tpage, temp, tpages, link) { + unpin_user_pages_dirty_lock(&tpage->page, 1, true); + list_del(&tpage->link); + kfree(tpage); + } +} + static void cove_delete_page_list(struct kvm *kvm, struct list_head *tpages, bool unpin) { struct kvm_riscv_cove_page *tpage, *temp; @@ -425,7 +437,8 @@ int kvm_riscv_cove_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) sbi_ext = kvm_vcpu_sbi_find_ext(vcpu, cp->a7); if ((sbi_ext && sbi_ext->handler) && ((cp->a7 == SBI_EXT_DBCN) || - (cp->a7 == SBI_EXT_HSM) || (cp->a7 == SBI_EXT_SRST) || ext_is_01)) { + (cp->a7 == SBI_EXT_HSM) || (cp->a7 == SBI_EXT_SRST) || + (cp->a7 == SBI_EXT_COVG) || ext_is_01)) { ret = sbi_ext->handler(vcpu, run, &sbi_ret); } else { kvm_err("%s: SBI EXT %lx not supported for TVM\n", __func__, cp->a7); @@ -451,7 +464,8 @@ int kvm_riscv_cove_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) return ret; } -int kvm_riscv_cove_gstage_map(struct kvm_vcpu *vcpu, gpa_t gpa, unsigned long hva) +static int kvm_riscv_cove_gstage_map(struct kvm_vcpu *vcpu, gpa_t gpa, + unsigned long hva) { struct kvm_riscv_cove_page *tpage; struct mm_struct *mm = current->mm; @@ -517,6 +531,35 @@ int kvm_riscv_cove_gstage_map(struct kvm_vcpu *vcpu, gpa_t gpa, unsigned long hv return rc; } +int kvm_riscv_cove_handle_pagefault(struct kvm_vcpu *vcpu, gpa_t gpa, + unsigned long hva) +{ + struct kvm_cove_tvm_context *tvmc = vcpu->kvm->arch.tvmc; + struct kvm_riscv_cove_page *tpage, *next; + bool shared = false; + + /* TODO: Implement a better approach to track regions to avoid + * traversing the whole list on each fault. + */ + spin_lock(&vcpu->kvm->mmu_lock); + list_for_each_entry_safe(tpage, next, &tvmc->shared_pages, link) { + if (tpage->gpa == (gpa & PAGE_MASK)) { + shared = true; + break; + } + } + spin_unlock(&vcpu->kvm->mmu_lock); + + if (shared) { + return sbi_covh_add_shared_pages(tvmc->tvm_guest_id, + page_to_phys(tpage->page), + SBI_COVE_PAGE_4K, 1, + gpa & PAGE_MASK); + } + + return kvm_riscv_cove_gstage_map(vcpu, gpa, hva); +} + void noinstr kvm_riscv_cove_vcpu_switchto(struct kvm_vcpu *vcpu, struct kvm_cpu_trap *trap) { int rc; @@ -804,6 +847,7 @@ void kvm_riscv_cove_vm_destroy(struct kvm *kvm) cove_delete_page_list(kvm, &tvmc->reclaim_pending_pages, false); cove_delete_page_list(kvm, &tvmc->measured_pages, false); cove_delete_page_list(kvm, &tvmc->zero_pages, true); + cove_delete_shared_pinned_page_list(kvm, &tvmc->shared_pages); /* Reclaim and Free the pages for tvm state management */ rc = sbi_covh_tsm_reclaim_pages(page_to_phys(tvmc->tvm_state.page), tvmc->tvm_state.npages); diff --git a/arch/riscv/kvm/cove_sbi.c b/arch/riscv/kvm/cove_sbi.c index 01dc260..4759b49 100644 --- a/arch/riscv/kvm/cove_sbi.c +++ b/arch/riscv/kvm/cove_sbi.c @@ -380,6 +380,24 @@ int sbi_covh_add_zero_pages(unsigned long tvmid, unsigned long page_addr_phys, return 0; } +int sbi_covh_add_shared_pages(unsigned long tvmid, unsigned long page_addr_phys, + enum sbi_cove_page_type ptype, + unsigned long npages, + unsigned long tvm_base_page_addr) +{ + struct sbiret ret; + + if (!PAGE_ALIGNED(page_addr_phys)) + return -EINVAL; + + ret = sbi_ecall(SBI_EXT_COVH, SBI_EXT_COVH_TVM_ADD_SHARED_PAGES, tvmid, + page_addr_phys, ptype, npages, tvm_base_page_addr, 0); + if (ret.error) + return sbi_err_map_linux_errno(ret.error); + + return 0; +} + int sbi_covh_create_tvm_vcpu(unsigned long tvmid, unsigned long vcpuid, unsigned long vcpu_state_paddr) { diff --git a/arch/riscv/kvm/vcpu_exit.c b/arch/riscv/kvm/vcpu_exit.c index c46e7f2..51eb434 100644 --- a/arch/riscv/kvm/vcpu_exit.c +++ b/arch/riscv/kvm/vcpu_exit.c @@ -43,7 +43,7 @@ static int gstage_page_fault(struct kvm_vcpu *vcpu, struct kvm_run *run, if (is_cove_vcpu(vcpu)) { /* CoVE doesn't care about PTE prots now. No need to compute the prots */ - ret = kvm_riscv_cove_gstage_map(vcpu, fault_addr, hva); + ret = kvm_riscv_cove_handle_pagefault(vcpu, fault_addr, hva); } else { ret = kvm_riscv_gstage_map(vcpu, memslot, fault_addr, hva, (trap->scause == EXC_STORE_GUEST_PAGE_FAULT) ? true : false); diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c index d2f43bc..8bc7d73 100644 --- a/arch/riscv/kvm/vcpu_sbi.c +++ b/arch/riscv/kvm/vcpu_sbi.c @@ -13,6 +13,8 @@ #include <asm/kvm_nacl.h> #include <asm/kvm_cove_sbi.h> #include <asm/kvm_vcpu_sbi.h> +#include <asm/asm-offsets.h> +#include <asm/kvm_cove.h> #ifndef CONFIG_RISCV_SBI_V01 static const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_v01 = { @@ -32,6 +34,14 @@ static const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_pmu = { }; #endif +#ifndef CONFIG_RISCV_COVE_HOST +static const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_covg = { + .extid_start = -1UL, + .extid_end = -1UL, + .handler = NULL, +}; +#endif + struct kvm_riscv_sbi_extension_entry { enum KVM_RISCV_SBI_EXT_ID dis_idx; const struct kvm_vcpu_sbi_extension *ext_ptr; @@ -82,6 +92,10 @@ static const struct kvm_riscv_sbi_extension_entry sbi_ext[] = { .dis_idx = KVM_RISCV_SBI_EXT_VENDOR, .ext_ptr = &vcpu_sbi_ext_vendor, }, + { + .dis_idx = KVM_RISCV_SBI_EXT_COVG, + .ext_ptr = &vcpu_sbi_ext_covg, + }, }; void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, struct kvm_run *run) diff --git a/arch/riscv/kvm/vcpu_sbi_covg.c b/arch/riscv/kvm/vcpu_sbi_covg.c new file mode 100644 index 0000000..44a3b06 --- /dev/null +++ b/arch/riscv/kvm/vcpu_sbi_covg.c @@ -0,0 +1,232 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2023 Rivos Inc. + * + * Authors: + * Rajnesh Kanwal <rkanwal@rivosinc.com> + */ + +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/kvm_host.h> +#include <linux/list.h> +#include <linux/mm.h> +#include <linux/spinlock.h> +#include <asm/csr.h> +#include <asm/sbi.h> +#include <asm/kvm_vcpu_sbi.h> +#include <asm/kvm_cove.h> +#include <asm/kvm_cove_sbi.h> + +static int cove_share_converted_page(struct kvm_vcpu *vcpu, gpa_t gpa, + struct kvm_riscv_cove_page *tpage) +{ + struct kvm *kvm = vcpu->kvm; + struct kvm_cove_tvm_context *tvmc = kvm->arch.tvmc; + int rc; + + rc = sbi_covh_tvm_invalidate_pages(tvmc->tvm_guest_id, gpa, PAGE_SIZE); + if (rc) + return rc; + + rc = kvm_riscv_cove_tvm_fence(vcpu); + if (rc) + goto err; + + rc = sbi_covh_tvm_remove_pages(tvmc->tvm_guest_id, gpa, PAGE_SIZE); + if (rc) + goto err; + + rc = sbi_covh_tsm_reclaim_page(page_to_phys(tpage->page)); + if (rc) + return rc; + + spin_lock(&kvm->mmu_lock); + list_del(&tpage->link); + list_add(&tpage->link, &tvmc->shared_pages); + spin_unlock(&kvm->mmu_lock); + + return 0; + +err: + sbi_covh_tvm_validate_pages(tvmc->tvm_guest_id, gpa, PAGE_SIZE); + + return rc; +} + +static int cove_share_page(struct kvm_vcpu *vcpu, gpa_t gpa, + unsigned long *sbi_err) +{ + unsigned long hva = gfn_to_hva(vcpu->kvm, gpa >> PAGE_SHIFT); + struct kvm_cove_tvm_context *tvmc = vcpu->kvm->arch.tvmc; + struct mm_struct *mm = current->mm; + struct kvm_riscv_cove_page *tpage; + struct page *page; + int rc; + + if (kvm_is_error_hva(hva)) { + /* Address is out of the guest ram memory region. */ + *sbi_err = SBI_ERR_INVALID_PARAM; + return 0; + } + + tpage = kmalloc(sizeof(*tpage), GFP_KERNEL_ACCOUNT); + if (!tpage) + return -ENOMEM; + + mmap_read_lock(mm); + rc = pin_user_pages(hva, 1, FOLL_LONGTERM | FOLL_WRITE, &page, NULL); + mmap_read_unlock(mm); + + if (rc != 1) { + rc = -EINVAL; + goto free_tpage; + } else if (!PageSwapBacked(page)) { + rc = -EIO; + goto free_tpage; + } + + tpage->page = page; + tpage->gpa = gpa; + tpage->hva = hva; + INIT_LIST_HEAD(&tpage->link); + + spin_lock(&vcpu->kvm->mmu_lock); + list_add(&tpage->link, &tvmc->shared_pages); + spin_unlock(&vcpu->kvm->mmu_lock); + + return 0; + +free_tpage: + kfree(tpage); + + return rc; +} + +static int kvm_riscv_cove_share_page(struct kvm_vcpu *vcpu, gpa_t gpa, + unsigned long *sbi_err) +{ + struct kvm_cove_tvm_context *tvmc = vcpu->kvm->arch.tvmc; + struct kvm_riscv_cove_page *tpage, *next; + bool converted = false; + + /* + * Check if the shared memory is part of the pages already assigned + * to the TVM. + * + * TODO: Implement a better approach to track regions to avoid + * traversing the whole list. + */ + spin_lock(&vcpu->kvm->mmu_lock); + list_for_each_entry_safe(tpage, next, &tvmc->zero_pages, link) { + if (tpage->gpa == gpa) { + converted = true; + break; + } + } + spin_unlock(&vcpu->kvm->mmu_lock); + + if (converted) + return cove_share_converted_page(vcpu, gpa, tpage); + + return cove_share_page(vcpu, gpa, sbi_err); +} + +static int kvm_riscv_cove_unshare_page(struct kvm_vcpu *vcpu, gpa_t gpa) +{ + struct kvm_riscv_cove_page *tpage, *next; + struct kvm *kvm = vcpu->kvm; + struct kvm_cove_tvm_context *tvmc = kvm->arch.tvmc; + struct page *page = NULL; + int rc; + + spin_lock(&kvm->mmu_lock); + list_for_each_entry_safe(tpage, next, &tvmc->shared_pages, link) { + if (tpage->gpa == gpa) { + page = tpage->page; + break; + } + } + spin_unlock(&kvm->mmu_lock); + + if (unlikely(!page)) + return -EINVAL; + + rc = sbi_covh_tvm_invalidate_pages(tvmc->tvm_guest_id, gpa, PAGE_SIZE); + if (rc) + return rc; + + rc = kvm_riscv_cove_tvm_fence(vcpu); + if (rc) + return rc; + + rc = sbi_covh_tvm_remove_pages(tvmc->tvm_guest_id, gpa, PAGE_SIZE); + if (rc) + return rc; + + unpin_user_pages_dirty_lock(&page, 1, true); + + spin_lock(&kvm->mmu_lock); + list_del(&tpage->link); + spin_unlock(&kvm->mmu_lock); + + kfree(tpage); + + return 0; +} + +static int kvm_sbi_ext_covg_handler(struct kvm_vcpu *vcpu, struct kvm_run *run, + struct kvm_vcpu_sbi_return *retdata) +{ + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + uint32_t num_pages = cp->a1 / PAGE_SIZE; + unsigned long funcid = cp->a6; + unsigned long *err_val = &retdata->err_val; + uint32_t i; + int ret; + + switch (funcid) { + case SBI_EXT_COVG_SHARE_MEMORY: + for (i = 0; i < num_pages; i++) { + ret = kvm_riscv_cove_share_page( + vcpu, cp->a0 + i * PAGE_SIZE, err_val); + if (ret || *err_val != SBI_SUCCESS) + return ret; + } + return 0; + + case SBI_EXT_COVG_UNSHARE_MEMORY: + for (i = 0; i < num_pages; i++) { + ret = kvm_riscv_cove_unshare_page( + vcpu, cp->a0 + i * PAGE_SIZE); + if (ret) + return ret; + } + return 0; + + case SBI_EXT_COVG_ADD_MMIO_REGION: + case SBI_EXT_COVG_REMOVE_MMIO_REGION: + case SBI_EXT_COVG_ALLOW_EXT_INTERRUPT: + case SBI_EXT_COVG_DENY_EXT_INTERRUPT: + /* We don't really need to do anything here for now. */ + return 0; + + default: + kvm_err("%s: Unsupported guest SBI %ld.\n", __func__, funcid); + retdata->err_val = SBI_ERR_NOT_SUPPORTED; + return -EOPNOTSUPP; + } +} + +unsigned long kvm_sbi_ext_covg_probe(struct kvm_vcpu *vcpu) +{ + /* KVM COVG SBI handler is only meant for handling calls from TSM */ + return 0; +} + +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_covg = { + .extid_start = SBI_EXT_COVG, + .extid_end = SBI_EXT_COVG, + .handler = kvm_sbi_ext_covg_handler, + .probe = kvm_sbi_ext_covg_probe, +};

[RFC,41/48] RISC-V: KVM: Add host side support to handle COVG SBI calls.

Commit Message

Patch